Research

Class size is one of the key indicators of early childhood education’s structural quality. Nationwide, the average class size has been declining since 2010; however, prior research has yet to reach a consensus on the effect of class size reduction. Based on a follow-up survey conducted in 2017 to 2018 of preschool children in a Northeastern county in China, this study utilizes a multilevel value-added model to identify the impact of class size on child development measured by the East Asia-Pacific Early Child Development Scales (EAP-ECDs). Once controlling the baseline EAP-ECDs score, the class size of the K1 classroom has no significant effect on children’s performance at K2; K2 children in smaller classes perform significantly worse in K3 than their counterparts in regular or large K2 classes. The subgroup analysis shows that K2 children from rural households, low socioeconomic status families, or public kindergartens benefit more in K3 if they attend regular rather than large K2 classes. The robustness check demonstrates that the results are robust under alternative definitions for structural quality and child development. Class size reduction can improve the structural quality of early childhood education; however, it has not produced a homogeneous, positive, and significant effect on child development. There is a need for future research to identify the mechanisms behind class size reduction. 

The KIDSCREEN questionnaires effectively assess health-related quality of life (HRQoL) in children and adolescents and are widely used. This study evaluates the psychometric properties of the Mandarin Chinese KIDSCREEN-27 (KS-27) and KIDSCREEN-10 (KS-10) to meet the demand for shorter versions in China. We reanalyzed data from a cross-sectional survey of 4,385 adolescents (ages 11–17) conducted in Weifang City, China, in late 2016. A subsample of 841 adolescents was retested. We assessed the feasibility, reliability, and validity of the KS-27 and KS-10. We find that the KS-27 and KS-10 were completed in under 12.33 minutes, with a response rate exceeding 90%. Their psychometric properties were satisfactory, showing strong internal consistency (Cronbach’s alpha: 0.786–0.881) and excellent test-retest reliability (ICCs: 0.590–0.842). Confirmatory factor analysis supported their intended structures, and they demonstrated good convergent and discriminant validity. Known-group validity was confirmed with medium to large effect sizes related to socioeconomic and mental health status. The results of KS-27 and KS-10 showed strong criterion validity when compared to the KS-52. The KS-27 and KS-10 in Mandarin Chinese exhibit excellent psychometric properties, making them suitable tools for measuring HRQoL in Chinese children and adolescents.